Starving polar bears turn to cannibalism

[OKIsItJustMe]

http://www.thestar.com/news/sciencetech/environment/article/732010--starving-polar-bears-turn-to-cannibalism

Starving polar bears turn to cannibalism

2009/11/28 04:30:00

Scientists say shrinking Arctic sea ice may be forcing some polar bears into cannibalizing young cubs.

"When (bears) are very hungry, they go looking for something to eat," biologist Ian Stirling said Friday. "There's nothing much to eat along the Hudson Bay coast in the fall other than other bears."

So far this fall, tour operators and scientists have reported at least four and up to eight cases of mature males eating cubs and other bears in the population around Churchill, Man. Four cases were reported to Manitoba Conservation and four to Environment Canada.

"That's a very big number," said Stirling, a retired Environment Canada scientist, who has studied the Churchill population for 35 years. "I worked there well over 30 years and never saw a single case of cannibalism."

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[imdjh]

3. Everything I have seen on Nat Geo says mother polar bears have to keep the kids away from adults...

.... for this very reason, ie because adult males are pigs. This was before every "environmentalist" ended every sentence with "global warming".

[notesdev]

4. Getting tired of scare stories

trying to claim natural unpleasantness is mankind's fault.

We got enough that's our fault without inventing new stuff.

[pscot]

8. Nothing new about

what we're doing to the big predators. We've been systematically exterminating the competition for almost a million years. The last of them will be gone well before the end of this century. We can be proud. It's a remarkably ugly record of achievement. No other animal could or would have done it. Our savagery is matched only by our thoroughness.

[OKIsItJustMe]

5. So, the logical question is, “Why the apparent increase?”

Is this unusual, or is it just increased awareness on our part?

Is it a form of population control on the bears’ part? (are mothers doing a worse job of defending their cubs?)

http://animal.discovery.com/news/ap/20060612/polarbears.html

Study: Polar Bears Turning to Cannibalism

By Dan Joling, Associated Press

June 14, 2006 — Polar bears in the southern Beaufort Sea may be turning to cannibalism because longer seasons without ice keep them from getting to their natural food, a new study by American and Canadian scientists has found.

The study reviewed three examples of polar bears preying on each other from January to April 2004 north of Alaska and western Canada, including the first-ever reported killing of a female in a den shortly after it gave birth.

…

Polar bears kill each other for population regulation, dominance, and reproductive advantage, the study said. Killing for food seems to be less common, said the study's principal author, Steven Amstrup of the U.S. Geological Survey Alaska Science Center.

"During 24 years of research on polar bears in the southern Beaufort Sea region of northern Alaska and 34 years in northwestern Canada, we have not seen other incidents of polar bears stalking, killing, and eating other polar bears," the scientists said.

…

http://alaska.usgs.gov/science/biology/polar_bears/unusual_mortality.html

Mortality

• http://alaska.usgs.gov/science/biology/polar_bears/unusual_mortality.html#cannibalism">Observations of intraspecific predation by polar bears in the southern Beaufort Sea

Observations of intraspecific predation by polar bears in the southern Beaufort Sea

Intraspecific killing has been reported among polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus). Although cannibalism is one motivation for such killings, the ecological factors mediating such events are poorly understood. Between 24 January and 10 April 2004, we confirmed three instances of intraspecific predation and cannibalism in the Beaufort Sea. One of these, the first of this type ever reported for polar bears, was a parturient female killed at her maternal den. The predatory bear was hunting in a known maternal denning area and apparently discovered the den by scent. A second predation event involved an adult female and cub recently emerged from their den, and the third involved a yearling male. During 24 years of research on polar bears in the southern Beaufort Sea region of northern Alaska and 34 years in northwestern Canada, we have not seen other incidents of polar bears stalking, killing, and eating other polar bears. We hypothesize that nutritional stresses related to the longer ice-free seasons that have occurred in the Beaufort Sea in recent years may have led to the cannibalism incidents we observed in 2004.

http://www.springerlink.com/content/m518018263874231/?p=9712b15921b54ad8b63d762945e9a782π=9">Amstrup, S. C., I. Stirling, T. S. Smith, C. Perham, and G. W. Thieman. 2006. Recent observations of intraspecific predation and cannibalism among polar bears in the southern Beaufort Sea. Polar Biology, 29:997-1002.

[imdjh]

6. I read it as three incidences.

[OKIsItJustMe]

7. Please note that this study is from a few years ago

(I should have made that clearer.)

My point was that (according to the researchers) this is unusual behavior.